(88) Date of publication of the international search report: 9 February 2006
For two-letter codes and other abbreviations, refer to the "Guid-ance Notes on Codes and Abbreviations" appearing at the beginning-ning ofeach regular issue of the PCT Gamite.
SYSTEM AND METHOD FOR COOKING BRICKS
FIELD OF THE INVENTION
The invention relates generally to a system and method for loading uncooked bricks in a kiln car and for unloading the baked bricks from the kiln car which has multiple levels for supporting bricks and also for firing bricks.
BACKGROUND OF THE INVENTION
The bricks are classified under the North American Industrial Classification System (NAICS) as "Brick and Structural Clay Tile". Most bricks made in America are called "outdoor bricks" and are used in combination with wooden frames or concrete blocks for building exteriors. Additionally, paving bricks are used for sidewalks, streets and avenues. Bricks are commonly formed by extruding a mixture of clay, water and other known ingredients, but they can also be formed by pressure. After the bricks are formed, they can be heated or "cooked" at elevated temperatures in a
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oven to remove moisture and harden the bricks. The uncooked bricks are called "bricks in green", and have about 18% humidity. This moisture must be removed before the bricks can be useful. Outdoor bricks are commonly provided in standard sizes of 20.3 centimeters by 30.4 centimeters. In particular, the 20.3-centimeter green bricks typically have standard dimensions of approximately 6.09cmxl0.16cmx21.8cm and weigh from around 2.26 to 2.72 kilograms, and individual 30.48cm green bricks typically have standard dimensions of around 9.9cmx9 .9cmx31.75cm and weigh approximately 5.89 kilograms to 6.35 kilograms. If bricks that have a moisture content of 18% are introduced into an oven, the bricks would explode due to the rapid accumulation of steam inside the brick. To prevent the bricks from exploding, the bricks must first be dried in a dryer before being placed in the kiln. The furnaces, which are constructed of refractories, typically remain within a specific temperature range of 982.20 to 1204 ° C. At the manufacturing plants in the United States, kiln cars are typically used to transport green bricks through furnaces in the form of a system of
rail. For example, almost all bricks are fired in "tunnel kilns", which employ a continuous firing process to maximize the efficiency of the brick firing operation. The bricks are placed in the kiln cars that move through the kiln during the cooking process, the bricks enter the kiln in the uncooked state and leave the kiln in a cooked state. The amount of time the bricks should remain in the kiln depends on the size of the bricks and the way they are stacked on the kiln cars. The continuous movement of the kiln cars loaded through the kilns at such high temperatures requires that the structure and composition of the kiln cars be extremely durable. Conventional oven carts have a refractory base on the oven cart (ie, a cover) on which the bricks are stacked. The refractory base has a support system made of pyrophyllite or cerdierite. The most common practice today is to stack the bricks on a solid deck with 8 to 14 high runs and 3 bricks long with a space for cooking between these packages. This results in a package that is approximately 76.2 centimeters to 132.08 centimeters high by 66.04 centimeters deep. The width of the package is typically 6.09
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meters or more. The cooking rail between the packages is around 50.8 centimeters. The burners in the furnace ignite these lanes either from above or from the sides. For this type of cooking, the cart is pushed in increments, aligning the cooking rail with the burners after each "" push "(called" index thrust "). The bricks have also been stacked on an elevated deck and the burners they ignite below and above the load.With this practice, when the bricks are stacks of 8 to 14 runs high, the firing cycle is similar to the concept of firing index, typically 30-48 hours. to cook stacks of bricks that have a height of two bricks.The firing cycle that uses such stacks, for example, low stacks, dramatically shortens, depending on the characteristics of the raw material.The furnace car equipment is known for cooking ceramic products that are not bricks, where the team defines multiple levels within the height of an oven.This configuration of multiple levels produces a capacity of Increased cooking of the products. However, a conventional oven car kit has not
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been tough enough to support multiple levels of bricks. With an increase in fuel, capital and labor costs, there is a need for a system to load and unload an oven vehicle where the maximum number of bricks can be efficiently cooked, and at the same time, it can not cause wear and tear. premature in the oven car.
SUMMARY OF THE INVENTION
The present invention overcomes the disadvantages of the prior art and provides an improved method and system for loading bricks into a furnace car. In one embodiment, the present invention provides a furnace car having equipment that defines multiple vertical levels to support low brick stacking. As used in the present invention, the term "low stacking" refers to a stacking of bricks that is approximately two bricks high (typically two bricks high, but possibly less or more), such that the stacking has a relatively low vertical height. At least some of the components of the equipment can be constructed of silicon carbide, which has high strength properties,
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to support multiple levels of bricks. The ability to cook multiple levels of low stacks of bricks is highly efficient, since the configuration provides separation between relatively small bricks packages, thus improving circulation, convection and moisture removal between small brick packs, which have a thermal capacitance respectively lower than conventional large stacks. Conveniently cooking times are reduced. The capacity per car is also improved compared to the conventional single-level firing of a low stacking, and the capacity per car is not sacrificed significantly on stacks of traditional elevated bricks, which require much longer cooking times. The furnace car can be loaded and unloaded automatically with bricks according to a method of the invention. One embodiment of a method for loading bricks, according to the present invention, requires providing an oven car that has equipment that defines multiple levels of support, the equipment includes vertical poles made of silicon carbide, and wherein each of the Support levels include a plurality of horizontal support beams made of silicon carbide, each of the horizontal support beams is mounted so that
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extends between a pair of the posts, and a plurality of horizontal, generally parallel, cross beams extends between the supporting beams, the furnace car has opposite distal and proximal ends. The method also requires placing the furnace car between a first machine and a second machine, the first machine includes a first car with a conveyor belt, the second machine includes a second car with rollers, the near end faces the first car, and the distal end faces the second car, the second car has a plurality of separate rollers and places a low stack of bricks that has to be cooked on the conveyor belt of the first car. The embodiment establishes the positioning of the first and second wagons in a position where the separate rollers of the second wagon arise between the transverse beams and extend vertically above a level selected from among the multiple levels of support. In addition, this modality involves activating the conveyor belt of the first car and the rollers of the second car to transport a low stack of bricks from the first car to the second car.; and lower the second car until the low stack of bricks lies directly on the transverse beams of the first level of the furnace car. The second car is then horizontally removed until
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that is released from the team. In an additional refinement of this embodiment, the step of placing the first and second carriages in a position where the separate rollers of the second carriage arise between the transverse beams involves vertically moving the first carriage to a position where the conveyor belt is at a vertical height slightly lower than a selected level of the multiple support levels, with the second car extending horizontally below the selected level to a position where the second car is adjacent to the first car, and raising the first and second cars so that the separate rollers of the second wagon arise between the transverse beams and extend vertically above the selected level. A method to download is also provided, in which generally the loading steps are executed in reverse. In an additional refinement of the method for unloading, the transverse beams are rotated after unloading the bricks. In one embodiment, according to one aspect of the invention, the vertical posts of the equipment are securely fixed relative to the frame of the oven car. The vertical posts can be fixed securely using refractory concrete. One advantage is that the automated loading and unloading of the bricks from the
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equipment, it can be run more reliably and accurately. More particularly, the fixed poles securely hold the furnace in a predetermined position relative to the frame such that the loading / unloading machine can be reliably positioned in relation to the equipment and the brick stacks therein. In a further embodiment, a system for loading a kiln car is provided. The system includes, for example, a furnace car having equipment with multiple levels and proximal distal ends, where the equipment is constructed using silicon carbide support posts for vertical support, and wherein each of the multiple levels includes main support beams of silicon carbide with transverse beams to receive the bricks that are placed between the main support beams; a first machine comprises a first car containing a conveyor belt and means for energizing the conveyor belt; and a second machine comprising a second car containing rollers and a means for energizing the rolls wherein the rolls are configured to extend above the multiple horizontal beams when the second car extends below the base of the oven car and rises until the rollers are placed above the
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the horizontal beams, and wherein the distal end of the furnace car is adjacent to the first car and the proximal end of the furnace car is adjacent to the second car. It has been found that the oven car of the present invention is highly durable and allows a configuration of high capacity bricks which can be cooked efficiently without premature wear of the oven car. The brick configuration also provides the most efficient cooking while minimizing the amount of defective product. Because the bricks are only stacked to a maximum level of two bricks, there is less breakage of the bricks as well as less defective product. Furthermore, it is estimated that the useful life of the furnace car of the present invention is much longer than the useful life of conventional furnace cars. In addition to reducing capital costs, the present invention can lead to lower fuel consumption while producing bricks of better quality. Additional features and advantages of the present invention will be apparent from the description, claims and figures presented herein.
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BRIEF DESCRIPTION OF THE FIGURES
Figure 1 is a deployment of the system for processing bricks according to one embodiment of the invention. Figures 2A-2D illustrate the loading of a kiln car with bricks using a first wagon containing a conveyor belt and a second wagon containing rollers according to one embodiment of the invention. Figures 3A-3C illustrate the loading of a kiln car with bricks using a scaffold with a fork in accordance with one embodiment of the invention. Figure 4 is a schematic side elevation of a furnace car showing bricks loaded in a separate form according to a system and method having characteristics according to the teachings of the present invention. Figure 5 is a schematic top view of the oven cart of Figure 4. Figure 6 is a front elevation of the oven cart of Figure 4 including exemplary equipment constructed of refractory material to support bricks during cooking, which can be used according to the system and method of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Now referring to the figures, where similar numbers designate similar components, Figure 1 illustrates a system for processing bricks according to the present invention. According to a modality shown in Figure 1, the bricks are formed in green, such as by extrusion, and are loaded onto a first conveyor belt 15 in an extrusion area 10. The bricks are then moved, by energizing of the conveyor belt, to a loading area 20 where the bricks are loaded on a furnace carriage 1. The furnace carriage 1 moves through the entire system as a rail. After the kiln car is fully loaded with bricks, the kiln car moves to a brick maintenance area 30 where the kiln car is held until the dryer 40 has space available for the kiln car. When the space becomes available in the dryer 40, the oven car moves towards the dryer 40 which heats the bricks at a sufficient temperature for a sufficient time to reduce the moisture content of the bricks in such a way that they do not explode the enter the oven 50. After the bricks have dried sufficiently, the oven car enters the oven 50 which cooks the
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bricks at a sufficient temperature for a sufficient time to produce bricks that meet specifications generally known in the brick industry. After the bricks have been cooked sufficiently, the kiln car moves to a brick storage area 60 and then to an unloading area 70. The bricks are unloaded from the kiln car 1 on a conveyor 80. They move the bricks, by energizing the conveyor belt, to a packing area. Figures 2A-2D show the steps in sequence for loading the bricks in a baking cart 101 in the loading area 20 shown in Figure 1 according to one embodiment of the invention. In Figure 2A, the first wagon containing a conveyor belt 15 is shown loaded with bricks 5 and placed slightly below the horizontal support beams of an unoccupied level 35 of the kiln car 101. Each level of the kiln car includes beams of horizontal support 36 and transverse beams 38, wherein the transverse beams 38 will support the bricks 5 and the horizontal support beams 36 support the transverse beams 38. The horizontal support beams 36 lie on projections 105 that are fixed to vertical supports 200. Beams 105 may include a raised portion to help maintain
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the position of the horizontal support beams 36 as they lie on the projections. A first machine 125 supplies power to the first car containing a conveyor belt 15. A second car containing rolls 65 is placed on the opposite side of the oven cart 101. A second machine 135 supplies power to the second car containing the rolls 65. Figure 2B shows the second wagon containing the rollers extending on the kiln car so that the first wagon containing a conveyor belt 15 and the second wagon containing the rollers 65 are next to one another. In one embodiment of the present invention, wagon 65 is sufficient to support the full weight of loaded bricks 5. In another embodiment, wagons 15 and 65 can be interconnected to provide additional support for wagon 15 for wagon 65 during the stage of cargo. Figure 2C shows the first wagon containing a conveyor belt 15 and the second wagon containing the rollers 65 raised to a level slightly above the horizontal support beams of an unoccupied level of the kiln car 35. Spaces are provided between the rollers to allow the first and second wagons to pass through the transverse beams of the unoccupied level of the kiln car 35. Figure 2C further shows the bricks 5 being moved from the first wagon
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containing a conveyor belt 15 to the second car containing the rollers 65. After the bricks 5 have been transferred to the second car containing the rollers 65, the first car containing a conveyor belt 15 and the second car containing the rollers 65 are lowered, allowing the bricks to lie on the transverse beams of the furnace car, as shown in figure 2D. The second car is then removed from the oven car. In a refinement of this embodiment of the present invention, the transverse beams 38 of each level 35 of the kiln car 101 are rotated between firing and firing cycles to prolong the operational life of the transverse beams. This allows transverse beams to be constructed using materials, other than silicon carbide, which are generally less expensive, but also less durable, such as cordierite or mullite. Between the firing cycles, the crossbeams may start to warp due to heat. When rotating the transverse beams between cycles, the bending that occurs during a cycle is counteracted by the bending that occurs during a subsequent cycle in such a way that the transverse beams remain substantially horizontal. Figures 3A-3C illustrate the steps in sequence
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for loading an oven car 201 into the loading area 20 of Figure 1 according to a further embodiment of the present invention. After the bricks move out of the extrusion area 10 of Fig. 1, they are loaded onto the transverse beams 86 which have been shaped and shaped to lie on the horizontal support beams 85 of a furnace car '201. The transverse beams 86 loaded with bricks 5 are moved by means of a scaffolding 75 containing a fork 77 in one of the unoccupied modules 95 of a furnace car 201. In this embodiment, the horizontal support beams 85 support the transverse beams 86 and the Horizontal support beams 85 lie on the projections 105 which are fixed to the vertical supports 200. As discussed above, the transverse beams 86 can be rotated between firing cycles. In one embodiment, the transverse beams supporting the bricks during drying and firing are rectangular in cross section and lie in the corresponding depressions in the horizontal support beams. However, transverse beams having other configurations in cross section can be used. In another embodiment, the transverse beams have a circular cross-section to allow the transverse beams to rotate during drying and firing.
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the bricks to reduce the tension in the brick. In this embodiment, the corresponding depressions in the horizontal support beams are tapered in the contraction direction of the brick so that the circular transverse beams roll back to their original position after the bricks are removed. A wagon with energized rollers can be used to load and unload the transverse beams, in which case the wagon can include horizontal beams having depressions to receive the transverse beams that are similar to the depressions in the horizontal support beams of the kiln car. In Figure 3A, the scaffolding fork 75 lifts the transverse beams 86 loaded with bricks 5. In Figure 3B, the scaffolding 75 moves the transverse beams 86 containing the bricks 5 in an unoccupied module 95 of the kiln car 201. Figure 3C shows the transverse beams containing the bricks 5 loaded in a module of the furnace car and the fork of the scaffolding 75 removed from the module 95 of the furnace car 201. It can be seen that the bricks can be loaded in, or unloaded from the transverse beams 86 using an energized roller car or conveyor belt similar to the car 65 shown in Figures 2A-D. Figures 4-6 illustrate a kiln car 1
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loaded with bricks 5 according to a configuration of the invention. The baking car 1 is generally used to support bricks during drying within a dryer 40 and cooking in an oven 50, as shown in Figure 1. The baking cart 1 includes a frame 140 having wheels 180 running on the rails 182 to guide the oven car through the dryer 40 and the oven 50. To support bricks to be baked, the oven car 1 further includes an oven car kit 100 supported on the rack 140 The equipment 100 is constructed of a refractory material resistant to high temperature, such as silicon carbide. The equipment 100 includes vertical support elements 200, horizontal support beams 85 and transverse beams 86. The vertical support elements are anchored in steel cavities 120 in the frame of the kiln car 140 using refractory concrete, which secures the elements of vertical support 200 to the frame 140. In order to securely fix the vertical support elements in place, the position of the vertical support elements remains exact so that the automated loading and unloading of the bricks of the equipment 100 can be executed in a more efficient manner. trustworthy. Figure 4 shows a side view of a loaded furnace car, where the arrow shows the direction in which the car moves.
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oven through the oven 50. Figure 5 is a top view of the oven car of Figure 4. Figure 6 is a front view of the oven car of Figure 4. In Figure 6, the horizontal support beam 85 it is shown on the projections 105 which are positioned along the vertical support elements or posts 200. Alternatively, the vertical support elements can be formed with openings to support the horizontal support beams. In another alternative, pins may be provided to secure the horizontal support beams to the vertical support elements. In accordance with one aspect of the present invention, a system and method for loading uncooked, green bricks onto a baking cart in a particular configuration is provided to maximize the efficiency of its processing. As shown in Figures 4-6, for example, the configuration of the bricks, when the bricks are loaded on the levels of the kiln car, allows more efficient processing of the bricks through the dryer and the kiln. The bricks are stacked in a plurality of "low stacking" assemblies, each set having, for example, two bricks in height, 8 bricks in length and 6 bricks in width. Six sets of bricks occupy each level, but the number of sets per level may vary based on
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the dimensions of the oven. Each set of bricks is located between the vertical support beams of silicon carbide. An air space of approximately 10.16 centimeters occupies the area that is on the sides and at the top of the groups. This configuration allows the bricks to be heated individually, resulting in uniform temperatures in the bricks. As regards cooking, the drying process can be accelerated with the present invention because the hot air passes around the individual bricks. Faster cycles result in smaller ovens and dryers that have a significant impact on the capital expenditures of new plants. To further improve the efficiency of brick cooking, the oven car is configured to allow higher temperatures and faster heating of the bricks through the dryer and the oven. The oven car 100 equipment has multiple levels to hold the bricks. As illustrated in Figure 6, the equipment 100 includes silicon carbide support posts 200 for vertical support, which are anchored in steel cavities 120 in the frame of the kiln car 140 using refractory concrete. In one embodiment of the invention, the projections 105 are positioned along
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the vertical support posts 200 for supporting the horizontal support beams 85, which, in turn, support the transverse beams 86. As noted above, other shapes can be employed to vertically support the support beams 85, such as openings on support posts 200 or pins. In another embodiment, each of the multiple levels of the kiln car kit has horizontal silicon carbide support beams which are fixed to the vertical silicon carbide support posts. Transverse beams, which run between the horizontal support beams, lie on the horizontal support beams, where the transverse beams can be made of cordierite, mullite or silicon carbide. As noted above, the transverse beams can be rotated between firing cycles to prolong the life of the transverse beams. The transverse beams are adapted to receive a stack of bricks from a wagon containing rollers. The kiln car facilitates the stacking of the bricks in multiple levels, preferably four levels, but the number of levels can vary depending on the dimensions of the kiln. The levels of the kiln car kit are separated so that the hot gases from the kiln car can circulate heat between the respective levels
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in an independent way. The bricks are placed on the transverse beams so that they are heated individually, not in packs, passing the furnace gases around the individual bricks. The bricks can be stacked in a "low stack" up to two bricks high. This configuration provides a lower thermal capacitance per stack and consequently allows a faster heating rate, thus leading to faster firing cycles. The oven carriage frame is insulated with ceramic fiber in the area around the posts. Ceramic fiber has a much lower density than conventional refractory fiber that carries the load of bricks as well as insulating the frame of conventional baking trolleys. Because the density of the ceramic fiber is much lower than the density of the conventional refractory, less heat is required to heat the low mass ceramic fiber, thus saving fuel with the use of ceramic fiber. One embodiment for loading the oven car focuses on a first machine having a first car with a conveyor belt and a second machine having a second car with rollers. A stack of 2 high by 6 wide by 8 long bricks of 20.32 centimeters is placed on the conveyor belt of the first car. For
loading and unloading the furnace car of the present invention, a furnace car having multiple levels and proximal distal ends is placed between the first machine and the second machine so that the proximal end of the furnace car is adjacent to the first machine and the distal end of the furnace car is adjacent to the second machine. After the furnace car is placed between the two machines, the first car is placed at a level where the conveyor belt is slightly below a first level of the multiple levels of the furnace car. The second car is then placed so that the second car is on one side of the first car. The first and second carriages are then lifted to a position where the rollers of the second carriage extend above the transverse beams of the first level. The first machine energizes the conveyor belt and the second machine energizes the rollers to move the entire level of bricks from the first car to the second car. After the stack of bricks lies completely on the rollers of the second car, the second car is lowered until the stack of bricks lies on the transverse beams of the first level. The second car of the furnace car is then removed and the first car is taken back to its original position. Preferably, charging starts at the upper level and repeats until
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all levels are loaded. To download, the loading procedure is usually executed in reverse. After the kiln car loaded with baked bricks is placed between the two machines, the first wagon is placed at a level where the conveyor belt is slightly below a first level of the multiple levels of the kiln car. The second car is then placed so that the second car is next to the first car. The first and second carriages are raised to a position where the rollers of the second carriage extend above the transverse beams of the first level. The conveyor belt of the first car and the rollers of the second car are energized to move the entire level of bricks from the second car to the first car. After the brick stack lies completely on the conveyor belt of the first car, then the second car of the furnace car is removed. Preferably, the discharge starts at the lower level and moves up until the four levels are discharged. Another mode for loading and unloading a furnace car uses a loading machine that has a scaffold, which preferably contains a 2-axis Servo-Control Unit, and an arm with a fork to load and unload a whole level of bricks ( 2 high by 8 of
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width by 7 long of bricks of 20.32 centimeters) in a furnace car. The whole level of bricks is placed in more than one transverse beam which are lifted by the fork of the loading machine and are placed in the horizontal support beams of the furnace car. First, load the uppermost level of the kiln car and move down until all levels of the kiln car have been filled with bricks. When the kiln car is unloaded, the fork of the loading machine simply lifts the transverse beams that contain the bricks of the horizontal support beams of the kiln car. The discharge starts from the lower level and advances up until all levels of the kiln car are empty. All references, including publications, patent applications, and patents, mentioned herein are incorporated by reference as if each reference was individually and specifically indicated to be incorporated by reference and is stipulated in its entirety in the present invention. The use of the terms "a" "a" and "" the "" and reference similar in context to describe the invention (especially in the context of the following claims) will be construed as encompassing both the singular and the plural, unless specifically
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Indicate otherwise in this document or clearly contradict the text. The mention of ranges of values in the present invention is simply intended to serve as a short method to refer individually to each separate value that falls within the range, unless otherwise indicated herein, and each separate value is incorporated in the detailed description as if it had been recited individually. All methods described herein may be executed in any convenient order unless otherwise indicated in this document or the context clearly contradicts it. The use of any and all examples, or exemplary language (eg, "such as") provided herein, is merely intended to better illuminate the invention and does not imply a limitation of the scope of the invention unless otherwise claimed. No part of the description should be construed as indicating that an unclaimed item is essential to the practice of the invention. Here the preferred embodiments of the invention are described, including the best mode known to the inventors to carry out the invention. It should be understood that the illustrated embodiments are exemplary only, and should not be construed as limiting the scope of the invention.